No Time to Die is due for release on 3 April but fans have asked for it to be held back to the summer "when experts expect the epidemic to have peaked".
The open letter is from the founders of MI6 Confidential and The James Bond Dossier, James Page and David Leigh.
"It is time to put public health above marketing release schedules."
The letter, titled No Time for Indecision, continued: "With a month to go before No Time to Die opens worldwide, community spread of the virus is likely to be peaking in the United States.